The name "slip stroke" aptly describes allowing the stick to slide through the shooting hand during the practice or warmup strokes. This may help you to aim accurately (starting close to the white ball) before pulling back and you may find a slip stroke useful for warming and accustoming the muscles of the shooting arm to the upcoming final pool stroke, giving you added power and control.
Here a stop action high speed photo catches me in a practice stroke, with the cuestick in midstroke. Note carefully that my shooting hand is placed far forward at the end of the wrap close to the cue's decorative points.
